“Because it's there,” was all the justification George Mallory ever needed to climb Everest. Our aspirations are a good deal more modest than old George's – and we're banking on a more gratifying outcome - but the rationale is much the same. Why would you drive from sea level to Australia's highest coach road? We'd prefer to ask why wouldn't you, especially when that road, from Lakes Entrance on Victoria's Gippsland Coast to the alpine resort of Mount Hotham, is quiet, testing, beautiful and irrefutably there.
For most of us, the route to Hotham involves a schlep down the Hume before drawing a bead on Bright and then tackling countless switchbacks up to the snow. The road less travelled from the south is a very different proposition, a little more cryptic in its relief, teasing in and out of deep forest and high altitude plateaus, and the car we've chosen for the drive is also a vehicle that takes a little time to key into.
It's been over two decades since Mercedes-Benz last sold a car with a straight-six engine. The C36 AMG was the first co-developed model between Mercedes and its recently acquired go-faster arm from Affalterbach, and it spawned a little-known E36 sibling before being replaced by V8-engined 43 models within 24 months. Since then, straight-six superiority has been undeniably claimed by the mob down the road in Munich. The latest E53 AMG Coupe not only marks the return of the straight-six, but also includes mild hybrid tech, four-wheel drive, an electric compressor and a nine-speed transmission. New game, new rules.
Oil and gas rigs dot the horizon, shimmering through the haze like a raiding party of Wellsian Martians. Lakes Entrance is dressed to impress, all crisp spring sun, pert Norfolk Island pines and dazzling cabin cruisers on round trips to nowhere in particular, piloted by satchel-skinned sixty-somethings. The E53 Coupe blends in well here. There's something about it that smacks of reward; an undemanding and elegant piece of self-congratulation. It’s inoffensively mannered, mystifyingly mute and almost entirely lacking the spiky character and dynamic honing we've come to expect of the latest generation of AMG coupes. You could waddle from your forty-foot Sunseeker Portofino, jump into the Merc and hardly register the transition.
That said, we've driven here in Comfort mode, the endlessly tedious A1 made bearable by the E53's molasses ride quality, indoor-outdoor airiness of that pillarless body and the unremitting consideration of the cabin, with its sumptuous touch points, endlessly configurable screens and telepathic sensor array. The initial run up to Bruthen offers a gentle warm up, climbing up the inland scarp slope from Lakes Entrance and making first acquaintance with the Tambo River, a watercourse we'll get to know very well over the next hundred kilometres, before the stream temporarily arcs off to the east.
The E53's softer settings ease it into an effortless flow on these austral stretches of the Great Alpine Road, a languid throttle map and conservative transmission calibration seeing it indolently slur into higher gears early. The engine, with its slightly uncouth cold idle, warms to the task, the electric motor nestling between engine and gearbox delivering a seamlessly smooth swell of torque to 2500rpm, with the electric compressor filling any residual lag for another 500rpm. The 48v electrical system and integrated starter-alternator give the E53 the softest idle stop system I've ever encountered. Starting the car requires a button press and the engine is instantly at idle, with no cough of starter motor whatsoever. The Yokohama Advan Sport tyres are actually quieter on coarser surfaces, smooth bitumen causing their sipes to sing a little, up a semitone of harmonic frequency on the crown of the road, down one when cambering towards the gutter.
We pick up the queues of poplars marking the watercourse just south of Tambo Crossing. A horseshoe of red rock rises to our left as the road drops into a natural amphitheatre. This seems as good a time as any to snick the mode selector into Sport+ and give this boulevardier a prod. The result is instantly transformative. The air suspension firms up, the exhaust reports for duty, stability control eases back a notch, the throttle becomes noticeably more incisive and, best of all, the transmission no longer lazily upshifts. Above 4500rpm, the engine note hardens and by 5000rpm it's hauling hard, building an addictive purity of timbre. Peak power arrives at 6100rpm, all 320kW of it, after which the 6500rpm redline places a curfew on the fun. Switch into manual and the tight spacing of the gears allows you stay in this zone, where the E53 insouciantly shrugs off its 1925kg bulk through sweepers.
Corner radiuses tighten inexorably as the road climbs, and we jink off the Great Alpine Road for a tougher assignment, through the sassafras-choked snake that is the Cassilis road, all hasty patching, root bumps and coarse chip. Here you need to manage the AMG's weight a little more judiciously, carefully synching your steering inputs against the hysteresis of its pitch and roll axes. Big throttle openings allow you to hear the electric motor at work; a faint whine accompanied by instant 100% fills on the boost gauges. That triad of motor, compressor and all-wheel drive propels the E53 out of tighter corners with real verve but little drama. If you're looking to smear inky traces of carbon black up the road, balancing throttle against steering, sign up for a C63 instead.
The road burst out of the trees on the high pastures just beyond the ghost town of Cassilis, with its depleted gold reefs and scorched remnants of the 1939 fire that drove away the remaining inhabitants trying to scratch a living from the exhausted terroir. Pointing arrow straight at hills so green they look draped with snooker table baize, the road rollercoasters through cattle paddocks punctuated by stark gums and centuries-old game trails burnished into tan halfpipes contouring to the near horizon. You'll catch a glimpse of wedgetails through the glass roof - barn doors with beaks lazily circling on invisible thermals - before you rejoin the B500 just outside Omeo.
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From here the road climbs, in great undulating steps, each downslope a few metres shorter than the climbs, so altitude arrives slyly. Taking stock of the dynamics of this car isn't easy chiefly because its bandwidth is so great. Its shortcomings arrive at the extremes of its envelope, which isn't so surprising. In Sport+, the 2.6-turn lock-to-lock steering could use more heft and so immersive is the soundtrack that you yearn for a few more revs at the top end. When cruising, the ride is good on these optional 20-inch wheels, but I can't help wondering how much better it'd be with the standard 19s with their more benign sidewalls. Setting the suspension to a softer tune and dialling everything else up to maximum attitude in the car's Individual mode seems to hit the sweet spot.
I'm still no fan of the clumsy wand gearshifter, but accept that centre console real estate is, these days, often prioritised for infotainment controls. Speaking of which, it's also a shame this car doesn't come with MBUX, the brilliant operating system seen in the A-Class. Instead we get a late version of the COMAND architecture with no touchscreen functionality. It works well though, and it's hard to fault materials quality, with neat stitching, a high-carpeted transmission tunnel and an extravagantly delicious leather and Alcantara-trimmed sports steering wheel.
Snow gums begin to dominate the roadside with dusty glimpses of spring snow patches still clinging gamely to the south-facing slopes. The straggling carbuncle that is Mount Hotham Alpine Resort hoves into view, deserted but for a gang of currawongs systematically redistributing the contents of a dumpster. We keep going, past what has to be the most scenic view of any police station in Australia, cheekily punt the redline through the corrugated iron-lined tunnel and round a final few corners until we're at 1845 metres above sea level on the highest coach road in the country. Marked by a surveyor's cross, it's the finish line of this particular road trip, and we're here just as the sun dips down beneath the deep blues of the rolling foothills, a series of pastel slides growing darker to the western hinterlands. The snowfields of Mount Feathertop and the Razorback glow rosily luminescent as photographer Jacobs gears up for the hero shot, the E53 ticking and pinging cool in what feels like the final breath of winter.
There's a lot to this car, certainly more than I initially gave it credit for. The powertrain is a delight, almost a victim of its own brilliance in that it leaves you wanting even more. It’ll certainly require a huge technical leap for Munich to match it in BMW’s forthcoming 8 Series. The Bavarians will also be hard-pushed to equal the considered and measured loveliness of the Mercedes-AMG E53 Coupe, with its complex character that rewards time and distance. The eye-widening adrenalin spike of the E63 sedans might well be an easier sell to power-junkie Australians, but as an everyday proposition, I'd choose the left-field E53 Coupe without hesitation. The road less travelled might be a beguiling proposition - and more often than not there's a solid reason why the traffic goes elsewhere - but every once in a while it turns up something you’d rather keep to yourself.
Model Mercedes-AMG E53 Coupe 4Matic+
Engine 2999cc, inline 6cyl, dohc, 24v, mild hybrid, turbo, electric s/c
Max power 320kW @ 6100rpm
Max torque 520Nm @ 1800-4800rpm (770Nm system torque w/e-motor)
Transmission 9-speed automatic
Economy 8.7L/100km (claimed)